Well Belgium is the easiest. Both because its a single possession and because they haven't held it long. In fact ~1880 they haven't held it at all as Leopold's rule isn't established until 1885. Possibly after the scandal of Leopold's rule in the Congo rather than take it over themselves the Belgium government sells it to someone else. Germany might be the most likely option as by this time Bismarck has either relaxed his opposition to extra-European colonies or been removed himself and if say the scandal occurs earlier or Wilhelm II is somewhat less destructive of German diplomacy Britain especially wouldn't probably object and Germany would have the money.
For the Netherlands, even ignoring their possessions in the Americas the DEI are a collection of territories so they might end up split among different powers. However the exact causes might be difficult. I can see a couple of possibilities.
a) That for some reason the Netherlands and Japan ~1900-10 get into a rumble and no other party intervene. In this case the Dutch don't really have the resources to defend the DEI and Japan should have the resources to take them, although possibly not hold them all at this stage. However not sure you get a situation where no one interferes. Apart from the fact many western colonizers won't like Japan taking over the region, even if some Japanese aren't claiming it as a liberation of fellow Asians from western colonizers. Plus the strategic position of the colonies would have even Britain, as Japan's primary ally OTL would have kittens about the Japanese controlling such areas as would the Australians and French and possibly the Americans.
b) That there's a WWI similar to OTL but it ends up in a stalemate. If for some reason Germans has occupied and continues to control the Netherlands or alternative somehow the Dutch end up as a German ally the DEI would be a free fire zone for the allied powers as their too important both in themselves and their location to be left plus a lot of powers will want to grab areas before other allies do.
For France its much more difficult to see because its a major power and also its empire even by 1880 is so large. As such its likely that at least some areas would stay under French control. Most likely possibly Algeria which already has a significant French settlement and possibly parts of their American possessions as the US might use the Monroe doctrine as an excuse to intervene. Possibly the easiest way would be that Frederick III of Germany doesn't have his throat cancer and rules for at least a couple of decades. He would favour a more liberal and less militaristic Germany and hence is unlikely to alienate Britain and the two powers could end up with a defensive alliance, especially if for whatever reason the Germany-Russian alliance lapses and Russia and France combine.
In itself that would make war unlikely as the CP + Britain would be too powerful and neither Britain nor a liberal Germany are likely to be that eager to start a war. However an accident could spiral into a war - or possibly the Franco-Russian alliance think they will have American support for some reason? The resulting conflict ends with France heavily defeated. In that case much of the French empire, although I suspect not all, is likely to end up being transferred to other control. [British, German, Italian, Australia, Japanese, American etc if any/all of them are on the anti-French side. Mind you I could see at least some areas, in the more isolated parts of Africa for instance simply being seen as not we[;iorth the bother. Of course this assumes that Wilhelm II has a less anti-British mind-set but possibly a couple of decades of close Anglo-German relations could change this.
For Britain its more complex simply because of the sheer size of the British empire, including areas such as Canada, already a largely independent dominion - with more to follow in 1901-10 OTL - and India, as well as that it really needs a way of overcoming the dominance of the RN. Which makes it very difficult for anyone to get to most of the colonies. Germany as it showed could make a substantial challenge to Britain's naval power but with its own continental needs couldn't break it, unless you assume either extreme stupidity in British leadership or some tech or tactical breakthrough that quickly and at the right time negates that British naval power. Then a quick conquest of the British Isles could force a surrender and much of the empire being lost at the resulting settlement.
The only other option that comes to mind is that the US is markedly more aggressive and for whatever reason joins a combination against Britain. This would from this time period put Canada and the Caribbean colonies at great risk and if its a point, OTL from ~1910/15 onward where the US is building up a large navy itself then its strength combined with Germany's could forces a defeat and much of the colonial carve up. Who would get India and whether they could hold it plus what happens to Australia and New Zealand would be interesting questions.